Means for making rubber type.



No. 756,652. PATENTBD APR. 5, 1904. B. F. KERN & W. J. 0. JOHNSON.

MEANS FOR MAKING RUBBER TYPE.

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PATENTBD APR. 5 1904. B. r. KERN & w. J. 0. JOHNSON.

MEANS FOR MAKING RUBBER TYPE.

APPLICATION FILED AUG. 28, 1903.

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Patented April 5, 1904.

UNTTE STATES PATENT OFFICE.

BENJAMIN FRANKLIN KERN AND WALTER J. O. JOHNSON, OF CHICAGO, ILLINOIS;SAID JOHNSON ASSIGNOR TO HARRY S. FOLGER, OF CHI- OAGO, ILLINOIS.

MEANS FOR MAKING RUBBER TYPE- SPECIFIGATION forming part of LettersPatent No. 756,652, dated April 5, 1904.

Application filed August 28, 1903- To a, whom it may concern:

Be it known that we, BENJAMIN FRANKLIN KERN and WALTER J. O. JOHNSON,citizens of the United States, and residents of Chicago, Cook county,Illinois, have invented certain new and useful Improvements in Means forMaking Rubber Type; and we do hereby declare that the following is afull, clear, and exact description of the same, reference being had tothe accompanying drawings, and to the letters of reference markedthereon, which form a part of this specification.

The object of the invention is to simplify the manufacture of rubbertype by improvements in the apparatus used in making the same,comprising a matrix-holding plate of novel construction used incombination with an improved chase for forming the matrix andspacing-bars held from movement on the matrix-holding plate andproviding a strong, simple, and durable apparatus so constructed as toinsure the greatest accuracy and rigidity in molding.

The invention consists in the matters hereinafter described, and morefully pointed out and defined in the appended claims.

In the drawings, Figure 1 is a perspective view of a chase'embodied inour invention, showing the same inverted. Fig. 2 is a perspective Viewof a recessed matrix-holding plate. Fig. 3 is a similar perspective viewof one of the spacing-bars, showing the same inverted. Fig. i is atransverse section of the chase with the type therein and also of thematrix-holding plate containing plastic material and showing the partsseparated. Fig. 5 is a similar view showing the parts brought togetherin molding the matrix. Fig. 6 is a similar sectional view of thematrix-holding plate and the matrix therein with the spacing-bars inposition. Fig. 7 is a similar view showing the matrix-holding plate withthe rubber therein in the vulcanizer ready for vulcanizing. Fig. 8 is anenlarged detail of one corner of the matrix-holding plate with thematrix therein and the spacing-bars in position.

As shown in said drawings, A indicates a Serial No. 171,034. (No model.)

metal frame or chase, usually of cast metal and of the usualconstruction, adapted to hold the metal type or other raisedprinting-surface in the usual manner. Within the chase is provided aliner comprising bars of steel or other suitable material type-high inwidth and plain on one side for engagement with the type and onthe'other side extended laterally, as shown in Figs. a and 5, providinga raised flat rib at, extending completely around the inner margin ofthe chase flush with the type-faces when secured in said chase andthrough which said bars are riveted to the chase. Said chase is providedwith set-screws, as is usual, whereby the type is rigidly clamped inposition therein in the usual manner, and a plate of steel (0 which, ifpreferred, can be integral with the adjacent rib a, is riveted to saidend of the chase, thereby stiffening the chaseacross the end thereof.Dowels a are provided'at the corners of said chase and act to hold the 7same in register with the matrix-holding plate.

B indicates as a Whole a matrix holding plate provided with a centralrecess corresponding in length and breadth with the external dimensionsof the raised rib a of the chase A and of a depth slightly greater thanthe required thickness of thematrix, (indicated by X in Figs. 5 to 8,inclusive.) A raised rib b b is provided adjacent each end of saidrecess and each side thereof, as shown in Fig. 2, and parallel with theends and sides of the recess, respectively, and form agage to indicatethe quantity of plastic material for matrix to be filled into saidrecess previous to compression and also aiford a brace for the spacingbars. Between said ribs and the margins of the recess the face of saidplate is planed down sufficiently to bring the surface below the outerface of the plate on the outer side of the ribs, and a plurality ofthreaded apertures are provided within said recess along the ends andsides thereof adapted for engagement with screw-bolts 6 by means ofwhich said spacing-bars O are secured in po-.

sition therein. Apertures are provided at the corners of saidmatrix-holding plate complemental with the dowels a and adapted to bringthe chase and matrix-holding plate into exact register when broughttogether, as shown in Figs. 4 and 5, and, as shown, a spiral spring a)is provided on each dowel and bears against the matrix-holding plate Bwhen under compression and acts to lift the chase with its contents whenthe pressure is released.

The space-bars C, as shown, are four in number and fit closely in theends and sides of the recess in the plate B, and are of a length toafford a tight joint at each corner, the same, as shown, being miteredtogether at the ends. Said space-bars are of a thickness equal to thedesired thickness of the rubber type-sheet, and are of a width on thebottom equal to the width of the ribs on the chase and fit in theimpressionmade thereby, and are provided at the top on the outer edgewith an outwardly-directed relatively thin flange 0 of a widthcorresponding with the distance of the ribs 6 I) from the margin of therecess in said plate. Said spacing-bars are apertured to correspond withthe threaded apertures in the bottom of the recess and are provided withtransverse grooves in the top to permit excess of rubber to escapeduring vulcanizing.

The operation is as follows: The threaded apertures in the bottom ofsaid recess in said matrix-holding plate having been plugged saidmatrix-holding plate is placed upon a suitable base of any desiredkindas, for instance, the

bed of a press-and the matrix material X of any desired kind is filledinto the recess in said plate in sufficient quantity to form a matrix ofdesired thickness under maximum compression, the quantity used usuallyabout filling the recess to the top of the ribs 6 Z) before compression,as shown in Fig. 4. The chase, with the type or other relief surfacetherein which it is desired to impress upon the matrix, is next invertedover the matrixholding plate with the dowels a fitting into thecomplemental apertures in the corners of said plate, and pressure isapplied upon the chase, compressing the plastic material to the desiredconsistency and a uniform thickness. After the matrix is formed thechase is lifted off, the springs aiding in lifting the chase, and if thematrix is not sufficiently hard for molding purposes the same ishardened in any appropriate manner 'to a condition sufiicient to receivethe impression. The spacing-bars C are next secured in place by means ofthe screw-bolts, and inasmuch as the bottom of said spacing-bars or thatportion contacting with the matrix is of the same width as the width ofthe rib a on the chase said bars fit closely in the impression made bysaid ribs (0. When in position, the outer flanges 0 of said bars bearagainst the ribs 56, which afford a rigid brace at the top of saidspacing-bar against outward pressure. The rubber is next filled intosaid recess upon the matrix, and the matrix-holding plate is next placedin a vulcanizing-press D, as shown 5 in Fig. 7, and pressure applied inany desired manner, the thickness of the rubber molded being limited bythe thickness of the spacebars, as shown in Fig. 8, thus insuringuniformity of thickness for the sheet. In vulcanizing excess material ispermitted to escape from the mold through the grooves in the uppersurface of the space-bars.

Inasmuch as the rib (0', together with the thickness of the chase, istype-high said ribs provide an impression in the plane of the typefacesand into which the space-bars fit. As the space-bars may, of course, beof any. thickness, the type-sheet may be made any preferred thickness,and where the same spacebars are used in molding it is obvious that thetype-sheets formed from the several molds will be gaged accurately tothe same thick ness. Furthermore, inasmuch as said ribs 7) b afford apositive bearing for the flanges of said space-bars above the center ofthe same it is evident that no lateral displacement of said space-barsby canting or tipping can occur during the compression or vulcanizing ofthe rubber.

Obviously instead of ribs on the matrixholding plate projections ofother form may 4 be used adapted to be engaged by projections carried onthe spacing-bars, and many details of construction may be varied withoutdeparting from the principles of our invention.

We claim as our invention- 1. In an apparatus for molding rubber typethe combination with a chase having a raised rib extending around theinner margin of the same with its face in the plane of the typefaces, ofa matrix-holding plate havinga central recess of a Width and length toreceive said raised rib of the chase and adapted to contain plasticmaterial, a rigid projection adjacent each margin of said recess,spacingbars fitted within the recess, a projection on the outer sidethereof adapted to bear against the projections on the matrix-holdingplate and interfitting means on said chase and matrix-holding plateadapted to bring the same into register.

2. An apparatus for molding rubber type comprising a plate having acentral recess to receive matrix material, a raised integral rib inproximity with and at each side and each end of the recess and extendingparallel with the same, spacing-bars adapted to fit into the sides andends of the recess and bearing with their outer margins above theircenters against said ribs and a chase provided on its type side with araised rib extending around its inner margin having outer dimensionscomplemental with the recess in the matrix-holding plate and having awidth approximately equal to that of the bottom of the spacing-bars andinterfitting means on said matrix-holding plate and chase adapted tobring the same into register.

3. In a device of the class described the combination with a recessedplate adapted to receive the matrix material, of one or more raisedprojections on the face thereof arranged near the sides and ends of therecess, said plate being reduced in thickness between said projectionsand the recess,spacingbars fitting closely in the sides and ends of therecess and affording raised sides and end walls therefor andoutwardlyprojecting portions in the plane with their upper surfacesadapted to bear against the projections on the plate, a chase, a raisedrib on the face thereof the height of which together with the thicknessof the chase is approximately equal to the length of the type to besecured therein, said ribs fitting closely in the recess in said plateand having a width equal to the bottom portion ofthe spacingbars andmeans acting to bring said chase and matrix-holding plate into register.4. In a device of the class described the combination with a chase, of araised rib around the inner margin thereof extending type-high on thechase, a recessed plate adapted to receive plastic materialsuitable foramatrix and into which the ribs of the chase fit closely, means actingto bring said plate and chase into register adapting the matrix to beformed by compression thereby,said rib affording a plane marginsurrounding the matrix, spacebars having a width on the under side equalto the width of said ribs and adapted to be rigidly secured within saidrecess covering the plane margins of the matrix and a flange at the topof each spacing-bar adapted for positive bearing on said plate andholding said bars from displacement.

5. In a device of the class described the combination with amatrix-holding plate having a shallow recess therein adapted to containa matrix, of space-bars fitting closely in the sides and ends of therecess and affording raised side and end walls for the mold, meansadapted to secure the space-bars to the matrix-holding plate andmutually engaging projections on said space-bars and plate acting tohold said space-bars from displacement.

6. The combination with a recessed matrixholding plate, of a raised ribadjacent said recess and on each side and end thereof, spacebars adaptedto fit in said recess, projections at the top of each space-bar adaptedto bear against said ribs and to hold said bar from outward displacementwhereby said space-bars afi'ord rigid side and end walls above thematrix adapted to receive within the same material for type and saidspace-bars having flat transversely-grooved upper faces adapted invulcanizing for engagement by the platen of the vulcanizing-press andacting to limit the compression of said material in the mold by contactwith the space-bars.

7 In a device of the class described the combination with a recessedplate adapted to receive matrix material of a chase, an inner lining forthe chase permanently attached thereto and affording a raised ribtype-high on the face of the chase adapted to fit into said recess inthe plate and afford a plane margin for the matrix and space-barsadapted to be secured on said matrix and parts thereon above the centerthereof adapted to hold said bars from slipping under outward pressure.

8. Inadevice of the class described the combination with a chase, of aninner steel lining permanently secured thereto and having a flangeextending outwardly over the face of the chase affording a raised flatrib surrounding the inner margin of the chase type-high.

9. In a device of the class described the combination with a recessedplate adapted to re ceive a matrix, of a raised rib adjacent to thesides and ends thereof, a shoulder about the margin of said recessparallel with said ribs, a chase, a rib type-high on the face thereofadapted to fit closely between said shoulders and form a flat marginabout said matrix, space-bars adapted to seat in said flat margin andprovided with laterally-extending flanges adapted to contact with theribs of said plate and means for rigidly securing said spacebars inposition.

10. In a device of the class described a chase, an inner lining rigidlyengaged thereon and affording a raised rib on the face of said chase, amatrix-holding plate having a recess therein adapted to fit closelyabout said ribs, a rib at the sides and ends of said recess and paralleltherewith, the margin of said plate being lower at the inner side ofsaid rib than at the outer side thereof, space-bars adapted to seatwithin said recess and provided with a lateral projection adapted tocontact with the ribs on said plate, and means for bringing said chaseand plate into register with each other.

11. A matrix-plate comprising a plate having a centralshallow recess anda flat margin about said recess, said margin being lower at its inneredge than its outer edge and an upwardly-extending rib on said marginparallel with the sides and ends of the plate.

In testimony whereof we have hereunto subscribed our names 1n thepresence of two subscribing witnesses.

BENJAMIN FRANKLIN KERN WALTER J. O. JOHNSON.

Witnesses:

C. W. HILLs, A. C. ODELL.

